Phase-locked loops usually comprise an oscillator and a phase detector, to which an oscillator signal and a reference frequency signal are supplied. The phase detector compares a phase of the oscillator signal with a phase of the reference frequency signal. Periodically repeating signals can occur at an output of the phase detector especially in the case of digitally designed phase-locked loops which are in a phase-locked state. These signals can lead to undesirable signal components called “spurious emissions”. These disturbances are often found near oscillator frequencies which are a whole-number multiple of the reference frequency.